A review of the benchmark weight for northern hemisphere three-year-olds in feature spring races has led to a change ahead of this year's carnival.

Northern hemisphere three-year-olds have won the Melbourne Cup for the past two years, with Rekindling carrying 51.5kg in 2017 while last year Cross Counter won with 51kg.

Racing Victoria's Greg Carpenter said off the back of Cross Counter's win last year officials reviewed how the three-year-olds from the northern hemisphere were integrated into the Melbourne Cup weights.

"The first part has been concluded, with the review of the weight-for-age scale,," Carpenter told RSN927.

"What it showed was that the Australian weight-for-age scale and the table of allowances for northern hemisphere three-year-olds actually had them more favourably treated than their own weight-for-age scale in Europe.

"For example, a 3200-metre race on the first Tuesday of November we were giving them a four kilogram allowance against the older horses, which is the equivalent of eight pounds 10 ounces, and they were getting only seven pounds in the English scale.

"So, what we've done is we've amended the benchmark weight for northern hemisphere three-year-olds in the Melbourne Cup from 55-1/2-(kilograms) to 56-1/2. So instead of getting four kilos off the older horses, they will now get three."

Cross Counter was weighted 4.5kg below weight-for-age in the handicap.

Under the new scale, 4.5kg under weight-for-age for a northern hemisphere three-year-old would be 52kg.

Carpenter said the benchmark weight for northern hemisphere three-year-olds has also lifted 0.5kg in the Caulfield Cup and Cox Plate.